Interior (in garage) TPRV Receptor

[Robert Autrey]

I've just performed a re-inspection of an older home that didn't previously have a TPRV discharge pipe. The fix the seller did is nice, but it doesn't, by my interpretation, meet the requirements. First of all, this TPRV drain connects directly to the drainage system. That's not allowed is it? Second, that is not the required "indirect" waste receptor is it? I've always believed that an indirect receptor was a receptor that included an air gap and, Third, code [2003 IRC - P2803.6.1] says that the termination must be "readily observable" by the occupants. Doesn't that mean they need to be able to see any dripping that may be occurring? And, the pipe itself does not appear to meet the minimum pressure rating of 100 psi at 180-degrees F. This pipe is labeled 200 psi at 73-degrees. I never realized I was confused about this issue until today. Maybe I'm having a senior moment or something?

[Jerry Peck]

Robert,

It's all wrong, from using PVC to how they ran it, did not support it, and to its non-termination in that space.

[Robert Autrey]

Robert,

It's all wrong, from using PVC to how they ran it, did not support it, and to its non-termination in that space.

Jerry,
I thought I was right. I'm still a little confused about this "approved waste receptor" business and the fact that the code says "shall not be directly connected to the drainage system". Does that mean that an interior (to the structure) termination in approved receptor still cannot drain into the drainage system? That is what is appears to mean to me. So, even if it terminates in approved receptor, the drain from that receptor still has to terminate at the exterior and not into the drainage system - right?

[Gary Burnett]

Robert,
It can terminate to an inside or outside drain (approved waste receptor) but it must have an air gap. That would mean it is not directly connected.

[Jerry Peck]

It can terminate to an inside or outside drain (approved waste receptor)

Not really.

It is required to termite within the room or space the water heater is in, which precludes terminating outside.

Now, if you meant that it could terminate through an air gap in the space the water heater was in to a drain which then goes outside, that would be correct.


but it must have an air gap. That would mean it is not directly connected.

Correct.

[Robert Autrey]

Not really.

It is required to termite within the room or space the water heater is in, which precludes terminating outside.

Now, if you meant that it could terminate through an air gap in the space the water heater was in to a drain which then goes outside, that would be correct.

Correct.

So, this would be correct if:
a) It had the correct type of pipe (not plain PVC).
b) It had an air gap at the receptor instead of the solid connection it has.
c) The receptor did not drain into the drainage system, but to the exterior.

[Jerry Peck]

So, this would be correct if:
a) It had the correct type of pipe (not plain PVC).
b) It had an air gap at the receptor instead of the solid connection it has.
c) The receptor did not drain into the drainage system, but to the exterior.

c) The receptor COULD drain into the drainage system, but the discharge must first go through the air gap.

(underlining and bold are mine)
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.

- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.
- - 6. Discharge in a manner that does not cause personal injury or structural damage.
- - 7. Discharge to a termination point that is readily observable by the building occupants.
- - 8. Not be trapped.
- - 9. Be installed to flow by gravity.
- - 10. Not terminate more than 6 inches (152 mm) above the floor or waste receptor.
- - 11. Not have a threaded connection at the end of the piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.

[Scott Patterson]

I would not trust that cantilevered shelf that the 450+lbs water heater is sitting on!

[Robert Autrey]

c) The receptor COULD drain into the drainage system, but the discharge must first go through the air gap.

(underlining and bold are mine)
- P2803.6.1 Requirements for discharge pipe. The discharge piping serving a pressure-relief valve, temperature relief valve or combination valve shall:
- - 1. Not be directly connected to the drainage system.

- - 2. Discharge through an air gap located in the same room as the water heater.
- - 3. Not be smaller than the diameter of the outlet of the valve served and shall discharge full size to the air gap.
- - 4. Serve a single relief device and shall not connect to piping serving any other relief device or equipment.
- - 5. Discharge to the floor, to an indirect waste receptor or to the outdoors. Where discharging to the outdoors in areas subject to freezing, discharge piping shall be first piped to an indirect waste receptor through an air gap located in a conditioned area.
- - 6. Discharge in a manner that does not cause personal injury or structural damage.
- - 7. Discharge to a termination point that is readily observable by the building occupants.
- - 8. Not be trapped.
- - 9. Be installed to flow by gravity.
- - 10. Not terminate more than 6 inches (152 mm) above the floor or waste receptor.
- - 11. Not have a threaded connection at the end of the piping.
- - 12. Not have valves or tee fittings.
- - 13. Be constructed of those materials listed in Section P2904.5 or materials tested, rated and approved for such use in accordance with ASME A112.4.1.


Ah! I was not registering that word "directly" at #1. Thanks. Now I get it. Until I don't get it again. Geez? After eight years doing this, and 1,500+ inspections, you'd think I'd have all of this down cold. Sometimes it just seems to go away.

[Robert Autrey]

I would not trust that cantilevered shelf that the 450+lbs water heater is sitting on!

LOL... Thanks for mentioning it. Now I'll have sweet dreams!

[Richard Stanley]

Rob,
That unit should have a pan under it that drains to exterior or to a waste receptor also...

[Robert Autrey]

Rob,
That unit should have a pan under it that drains to exterior or to a waste receptor also...

Yes. I called out the need for a pan. Client didn't care.